package liquibase.sqlgenerator.core;
import java.util.ArrayList;
import java.util.List;
import liquibase.database.Database;
import liquibase.database.core.DB2Database;
import liquibase.database.core.DerbyDatabase;
import liquibase.database.core.FirebirdDatabase;
import liquibase.database.core.H2Database;
import liquibase.database.core.HsqlDatabase;
import liquibase.database.core.InformixDatabase;
import liquibase.database.core.OracleDatabase;
import liquibase.database.core.SybaseASADatabase;
import liquibase.database.core.SybaseDatabase;
import liquibase.database.structure.Column;
import liquibase.database.structure.Table;
import liquibase.database.typeconversion.TypeConverterFactory;
import liquibase.exception.ValidationErrors;
import liquibase.sql.Sql;
import liquibase.sql.UnparsedSql;
import liquibase.sqlgenerator.SqlGeneratorChain;
import liquibase.statement.AutoIncrementConstraint;
import liquibase.statement.core.AddColumnStatement;
public class AddColumnGeneratorDefaultClauseBeforeNotNull extends AddColumnGenerator {
@Override
public int getPriority() {
return PRIORITY_DATABASE;
}
@Override
public boolean supports(AddColumnStatement statement, Database database) {
return database instanceof OracleDatabase
|| database instanceof HsqlDatabase
|| database instanceof H2Database
|| database instanceof DerbyDatabase
|| database instanceof DB2Database
|| database instanceof FirebirdDatabase
|| database instanceof SybaseDatabase
|| database instanceof SybaseASADatabase
|| database instanceof InformixDatabase;
}
@Override
public ValidationErrors validate(AddColumnStatement statement, Database database, SqlGeneratorChain sqlGeneratorChain) {
ValidationErrors validationErrors = super.validate(statement, database, sqlGeneratorChain);
if (database instanceof DerbyDatabase && statement.isAutoIncrement()) {
validationErrors.addError("Cannot add an identity column to a database");
}
return validationErrors;
}
@Override
public Sql[] generateSql(AddColumnStatement statement, Database database, SqlGeneratorChain sqlGeneratorChain) {
String alterTable = "ALTER TABLE " + database.escapeTableName(statement.getSchemaName(), statement.getTableName()) + " ADD " + database.escapeColumnName(statement.getSchemaName(), statement.getTableName(), statement.getColumnName()) + " " + TypeConverterFactory.getInstance().findTypeConverter(database).getDataType(statement.getColumnType(), statement.isAutoIncrement());
alterTable += getDefaultClause(statement, database);
if (primaryKeyBeforeNotNull(database)) {
if (statement.isPrimaryKey()) {
alterTable += " PRIMARY KEY";
}
}
if (statement.isAutoIncrement()) {
AutoIncrementConstraint autoIncrementConstraint = statement.getAutoIncrementConstraint();
alterTable += " " + database.getAutoIncrementClause(autoIncrementConstraint.getStartWith(), autoIncrementConstraint.getIncrementBy());
}
if (!statement.isNullable()) {
alterTable += " NOT NULL";
} else if (database instanceof SybaseDatabase || database instanceof SybaseASADatabase) {
alterTable += " NULL";
}
if (!primaryKeyBeforeNotNull(database)) {
if (statement.isPrimaryKey()) {
alterTable += " PRIMARY KEY";
}
}
if (statement.isUnique()) {
alterTable += " UNIQUE ";
}
List<Sql> returnSql = new ArrayList<Sql>();
returnSql.add(new UnparsedSql(alterTable, new Column()
.setTable(new Table(statement.getTableName()).setSchema(statement.getSchemaName()))
.setName(statement.getColumnName())));
addForeignKeyStatements(statement, database, returnSql);
return returnSql.toArray(new Sql[returnSql.size()]);
}
private String getDefaultClause(AddColumnStatement statement, Database database) {
String clause = "";
Object defaultValue = statement.getDefaultValue();
if (defaultValue != null) {
clause += " DEFAULT " + TypeConverterFactory.getInstance().findTypeConverter(database).getDataType(defaultValue).convertObjectToString(defaultValue, database);
}
return clause;
}
private boolean primaryKeyBeforeNotNull(Database database) {
return !(database instanceof HsqlDatabase || database instanceof H2Database);
}
}